Posted
by
michael
on Wednesday September 01, 2004 @05:30PM
from the time-on-target dept.

BoomZilla writes "Reading Disney's alliteratively titled Practically
Perfect Pyrotechnics introduces the latest in firework launch technology.
Gone are the 'light blue touch paper and retire a safe distance' days. Shells
are now launched using compressed air. No burning black powder means no smoke
drifting over the residential neighborhoods, plus a safer show. Best of all the
new system is more precise and can launch shells higher than black powder,
enabling spectacular new effects. An additional article:
The future of theme park fireworks
covers some of the pros and cons of compressed air launch systems." We mentioned this earlier.

I'm not sure the launch charge contributes too much smoke, as I've found the charge which distributes the firework to create more -- usually
evidenced by a series of greyish clouds carried away by higher winds. Grand Finales have had so much smoke at heights to obscure some
of the fireworks themselves. Then there's the matter of where I live having a chronic fog/marine layer problem which has rendered the most
fantastic displays only so many noisy, colorful blurs. Even they cute smiley ones, like the mouse pattern Disney is so fond of.

The air in the Los Angeles/San Bernardino area can be pretty awful, which probably has a lot more to do with their efforts to decrease smoke. I visited the Grand Canyon years ago and heard sometimes the visibility, in the summer is
so poor you can't see across the canyon, thanks to smog from San Diego and Los Angeles/San Bernardino, hundreds of miles to the west. (Fortunately I was there in winter, which I highly recommend (South Rim open only), with 200+ miles of visibility.)

A word of advice: Try to avoid a down-wind position for fireworks as sulpherous ash may drift down into your eyes and it burns like H2S.

Agreed-
The advances that Disney has either driven or inspired involving the use of compressed air/water 'charges' are another example of improved controllability. The 'singing waters' fountains made so popular are also cases in point. Now if I can take that 'stomp rocket' that my kids use, and duct tape a little C-4 to the top of it- cool !

Yep. All modern car emissions are *so* far down on what they were. Another amusing fact - because of that, it's no longer possible to kill yourself by gassing yourself with car exhaust. When auto manufacturers put in catalysts and electronic control modules, there was a noticeable drop in suicide rates.

With all due respect, that's very dangerous bullshit. The killing element in car exhaust is CO (carbon monoxide), which is not totally removed by a catalysator . Yes, the amount is reducted (typically about 80-90%) but there's still plenty enough to kill you if you use the engine in a closed space.

I'd hate to have seen it in the 70's then. LA and Houston rate as the world's biggest shitholes I've had the misfortune to be around. LA wins the contest hands down on the smog issue. I see the damn smog from LA from 100's of miles away on a fairly frequent basis. Nasty.

It will be difficult to replace all of the colors produced by metals and other compounds used in fireworks- some of which are quite toxic (strontium, cadmium, arsenic, antimony, PVC plastic, etc.). It will also be much more expensive. But high nitrogen explosives and newer organic compounds have a lot to offer the field- including colors you can't get with the old standbys.

Some of the high nitrogen stuff I used to work with was pretty interesting. Lots of newer, potentially safer compounds are in the pipeline- mainly for military applications, but they can be bastardized to, er, recreational purposes.

I'm not sure the launch charge contributes too much smoke, as I've found the charge which distributes the firework to create more -- usually evidenced by a series of greyish clouds carried away by higher winds.

But, you see, that's just it. The higher-up smoke is blown away by winds. The launch smoke tends to linger more as it's lower and thus less influenced by the wind. Also, it tends to linger where there are people-the higher smoke doesn't get in people's lungs.

Next fallacy. Can't see across the Grand Canyon? This Grand Canyon that is separated from any smog source by hundreds of miles? Yeah, right, all of Orange County sends its fog to the Grand Canyon, without any dispersion.

You haven't been to the Grand Canyon on a high-smog day, have you? True, you can usually see across the canyon itself, but you can't look down the length of it, and side canyons may be obscured.

Sure, it may be smoggy, but blaming this on LA is pretty farfetched... the smog will dissipate in the hundreds of miles of desert between the two... hell, it's not smoggy in the desert 50 miles from LA.

That said, the guy above was either joking or trolling... I recently climbed a nearby mountain, and you could see the smog band pretty distinctly...

The Los Angeles basin isn't what the poster was referring to IMO, but east Los Angeles, and San Bernadino. Have you ever been out to Ontario or Riverside at 3pm on a stagnant July afternoon? I lived in Ontario for 2 years, and I'm not surprised in the least at the fact that San Bernadino county has the worst smog in the United States. Driving out there from Los Angeles in the summer, every single day you could see a thick blanket of black smog hovering above Pomona.

This was true in the mid 90's when I was growing up, and going to school out there. We used to have a lot of smog alerts and some days you couldn't see the nearby mountians. It's really gotten a lot better, I don't recall seeing a smog alert in recent years, much less a higher level one. The the progress that has been made in recent memory can continue, then hopefully smog will be something we complain about because of the very sensitive meters and not because we can see it.::Digitac

Interesting. I lived out there in 1998, having moved there from North LA county, it was quite bad. I seem to remember smog alerts, though I wasn't particularly attentive of such things. I just went out to Fontana not too long ago and it really wasn't that bad, but I had assumed it was just a fluke. Why is it getting better? Was all the pollution before the result of industrial pollution? Because surely there are more cars on the road.

Up till a month ago I worked in Rancho Cucamonga (just north of Ontario). I don't remeber any days where there were smog alerts (1999-2004). Though, I do remember plenty of days where I couldn't see the mountains through the smog, and I was only about 5 miles south of Mt. Baldy. Driving down from Apple Valley, I was often horrified that I would have to breate that crap for the next 9 hours or so. The Inland Empire area has some really nasty smog in the summer months.

No burning black powder means no smoke drifting over the residential neighborhoods, plus a safer show. Best of all the new system is more precise and can launch shells higher than black powder, enabling spectacular new effects.

But I like watching the billows of smoke drifting across the river! And if the fireworks go any higher, I won't be able to watch them from my computer desk! They'll be blocked by the balcony of the apartment above mine!

No powder used to lift the shell, means much more explosive powder that can be used in the shell. If you used 25% of the weight of the shell to lift it before, (I'm making numbers up.. anyone know the real numbers, please correct me) then now you can have a 25% bigger boom.. (roughly).. which makes me happy, i like to see big explosions..

Fireworks are launched by a classic blackpowder mortar system: there's a lofting charge in the launch tube (basically, a bag of gunpowder), and the shell (usually consisting of a bursting charge, a number of "stars", and filler to give it a spherical shape). Changing the lofting mechanism from gunpowder to compressed air won't make a bit of difference for the shell.

There are two major types of Class B fireworks in the world: the spherical (mostly Asian made) and the cylindrical (mostly American/European made). The Asian style uses a pre-fabricated hard casing so that filler is unnecessary for the shape of the shell; filler is used mostly for keeping the shell balanced in flight and to keep the stars spread out (helps with the nice round bursts). The American style uses a soft paper casing around a cardboard form. This is the

A typical 8" shell weighs about 3 pounds, of which about 1 ounce is the lift charge. Most of the weight comes from the shell casing (pressed glued paper) that holds the burst charge and the stars and keeps them together long enough for the stars to ignite when the timing fuse burns through to the burst charge. Disney is probably using 4" shells for most of their stuff, so figure a pound of shell with a tablespoon of lift charge.

For reference, the largest shell ever fired (the 36" Fat Man) weighed 800 pounds and was lifted 1400 feet in the air by 1/2 pound of black powder.

...people who've moved in since that time knew exactly what they were buying...a house/condo near a theme park renowned for its fireworks displays

There is a big difference between what's right, and the results of the US legal system.

Example: Small airports were built all over the country. Decades later, the land around them was made into housing developments. Then people sued to have the noisy airports restricted to the point they were no longer viable, or shut down altogether. They consistently win, because there are 100 irate homeowners vs. 30 people who want to preserve the pre-existing airport. Bye-bye airport. The ultimate irony is when the runway becomes the main street through the new subdivision that's built where the airport was, and all the subdivision streets have names like Blue Sky Place and Lindbergh Drive.

It's similar to developers leveling a beautiful stand of trees to pack as many little vinyl houses as possible into a congested suburban hell, and naming the subdivision Aspen Acres. I guess Fugly Houses Estates doesn't sound very good.

Maybe I'm getting even more cynical in my old age, but there seem to be fewer and fewer instances where Right and Reality coincide.

Thanks to Michaels Cooking the books and some finagling they had a pretty good looking quarter, last report, mostly due to the theme parks. They've been hemoraging cash on movies though, which should warm your heart.

Disney has shut down its cel animation studios and switched to a CG format (ever noticed how Mickey and Minnie tilt their heads down when facing the camera?), under a misguided belief about how the Pixar co-productions beat Disney's recent cel-animated productions at the box office. Disney will already be bleeding by the time its animation division realizes that Pixar's movies had a plot.

Pixar has only two movies left with Disney, titled The Incredibles and Cars. Once these complete their theatrical and home-video runs, Disney will be bleeding even more.

Disney relies on its back catalog for revenue. Watch Disney start bleeding again in 2023 when the Supreme Court invokes three strikes (hinted at in the Eldred opinion) against the Chastity Bono Act and a revamped Mickey Mouse joins the supporting cast in other animation studios' films. (Trademark law potentially bars other studios from casting Mickey in a leading role.)

Considering that they have decided to donate the patents on this invention to a non-profit group I would say that we should all like/respect Disney at least a tad. That's a great move.

It may be, but I'd want a bit more information about the details before making such an assumption. If they were donating the techniques to the public domain, then it'd probably b okay to assume it's a good thing.

My potato guns use a customized ignition like what you're describing. The guns themselves are PVC, and the ignition is a camera flash circuit wired through a car ignition coil, which goes into a spark plug. Hairspray shoots the potatoes a good 150 yards if you wedge them in there enough.

Slightly more on-topic though, a friend of mine has a real nice compressed air potato gun that has an electronically triggered poppet valve. Despite the fact that his gun cost much more and is so much more complex, mine shoots more rapidly, farther, and louder. They both get a nice cloud of smoke out the barrel after the shot though. His because of the rapid decompression, and mine because of the burning hairspray. Surprisingly, we have mutual respect for each other's designs and we don't really compete with each other so much as help with design and construction problems.

My next gun will be compressed air, and once I figure it out with PVC, I'm moving on to stainless steel to hopefully get a supersonic potato (or other projectile) gun:-)

My next gun will be compressed air, and once I figure it out with PVC, I'm moving on to stainless steel to hopefully get a supersonic potato (or other projectile) gun:-)

I've been idly investigating this myself. It looks like there are high-pressure solenoid valves [google.com] available that are commonly used in hydraulic systems and Nitrous Oxide applications. They have ratings as high as 4500 PSI. The larger ones can be very expensive, but for a reasonable application such as this one, one might be able to keep the

You'll have to take this with a grain of salt... I'm a mechanical engineer, and I studied thermodynamics (read: nozzle calculations among other things), but it's been years since I was involved in that aspect of things (I'm more into mechanical components)

Now that the qualifier is done... It's going to be hard to get a potato gun supersonic. First, according to the calculations, getting supersonic flow out of compressed air requires a converging/diverging nozzle*. Subsonicly, as the tube diameter decr

I'm a mechanical engineering student myself, and I already realize a lot of what you're saying, but keep in mind that the speed of sound changes along with a change in pressure. Thermo/fluids wasn't my strong suit, but I think that it's possible to make it go supersonic by just using enough pressure. Think about this: an explosive supersonic projectile is nothing more than REALLY high pressure gasses (with different properties, but still...)

You also might not want to shoot actual potatos, unless you're looking to make hash browns at mach 2. Very little structural stability, a potato has.:)

I know that projectiles can go supersonic, I just am missing how the calculations work for it. Must have to do with the lack of unrestricted flow... If you're still in school, how about asking a prof? All the MEs I

If you use a poppet valve and a cheap solenoid valve you can get better results, this is what my friend uses. If you don't know, a poppet valve holds itself shut with the air pressure in the chamber, and when you release the pressure behind it, the larger volume of air in front of it pushes it out of the way, and then rushes into the barrel, projecting the potato out very quickly. The seals around the valve don't need to be very good because it only needs to work

Atually, the BATF (Alcohol, Tobacco and Firearms, what more do you need?) explicitly do not classify a potato cannon as a firearm requiring a license. Here's some kid's copy of the standard letter [ucsb.edu] but the meat of the matter is this:

The Bureau has previously examined devices known as "Spud Guns, Potato
Guns, or Spudzookas" and have determined that such devices, in and of
themselves, are not firearms as defined in Title 18 United States Code
(U.S.C.), Chapter 44, S 921(a)(3) or 26 U.S.C., Chapter

Be careful, though... for example, in Massachusetts, potato guns using hairspray are considered firearms (as they use an ignited material, or something)*. Last I heard (and don't take my word for it even if you're here), a compressed air gun is legal without a licence.

I prefer to consider the BAFT a Department, rather than a Bureau, don't you?

* and as it's a custom firearm, it might require a higher class licence, even, but I'm not sure about that.

Hairspray gummed up the works while I used a bolt-to-bolt spark gap. Now that I have a spark plug, it's not a problem (plus I wash it down after every session). Also, the flash circuit generates 300V that goes through an ignition coil that's only supposed to have 12v... so who knows how many volts that has at the spark plug? It's more than enough to break through any residue that the hairspray leaves on the plug.

I just find it amusing that Disney released all this news about their revolutionary, wonderful new launch system and then proceeded to roll out a new pyrotechnic show at Disneyland that, by all accounts, is disappointing at best compared to the one it replaced. Sure, it may be less polluting, but it's also a lot less fun.

Sure, there are other factors that caused the switch in shows, but the timing was unfortunate. They basically managed to associate environmentally friendly fireworks with totally boring fireworks, which, by an inspection of their description of the new launch technique, really isn't the case at all.

I don't get how you think this all means death. First off, many people launch potato cannons, and unless you look down the barrel, not much is going to hurt you. Added fireworks, its still safer than the same person launching one normally (no fire during liftoff). And as someone pointed out, it wouldn't be incredibly hard to rig it up electronically. Nothing with fire and bang will ever be 100% if you DIY, but its still probably safer than just shooting it off normally...

From the article:
The air-launch technology is such a revolutionary step forward that Disney has decided to share it with the pyrotechnics industry as a whole. The Walt Disney Company plans to donate the seven patents produced for the air-launch process to a non-profit group that will license the technology to the rest of the pyrotechnics industry.
Cool article, shocking conclusion. Must now re-evaluate opinion of Disney...

"Gone are the 'light blue touch paper and retire a safe distance' days.

You go ahead and stand next to the mortar if you want, but there are plenty of other ways for that round to cook off prematurally, not to mention what'll happen if a compressed air hose (enough to send a hefty shell 200+ feet into the air) bursts. Sure, the accident ratio will probably drop dramatically, but I'll keep my distance just the same.

Besides, normal ignition techniques will still be around for some time to come, if only beca

When I read this article the first time [slashdot.org], I emailed it to a friend of mine who works in the Pyrotechnics division at Disney World, and he replied saying that he didn't know what prompted them to write that article when they did -- Disney has been using that technology for several years now. Oh well, I guess old news is still news. Maybe it was just a slow news day the first time/. had that article, and an even slower news day this time...

Yeah, I remember a talk on this (maybe informal) back at the PGI http://www.pgi.org/ [pgi.org] convention in the mid 90-s. Talk was about including nitrocellulose casings (to reduce ash fallout) and RFID-like fuses in the shells for burst timing and ignition. A cap would be charged and time delays set via the touchless link.

I just assumed it's been that way for a while, and suprised that this hit as "news".

I could of swore a few years ago a friend told me about alternative rocket launching abilities. She lived in some hot desert place in America (Texas maybe..) and said they used compressed air or something similar to launch rockets because black power was too dangerous in the heat.

Why does it matter if Mickey mouse is now doing it? I was under the impression people at Slashdot were beyond Disney's target audience..

I took my wife and kids to Disneyland in Anaheim to check out the display. I have some video of it that isn't quite ready for web display (or should I say, I'm too busy:-), but suffice it to say it's a different show. They actually had two displays on July 4th, with slightly different timings and effects.

After seeing the same sort of fireworks for decades, I think it was more interesting than the old fire up and go boom. The most noticeable change is they can do much higher quality synchronized launches. One effect (a little overused) fired off a bunch of streamers in sequence at different angles, and because the flaming bits are not powered after launch, they have a nice regular parabolic trajectory. Nice effect.

However, they have a great Grand Finale either way. It's also nice to know my $150 worth of tickets went to something donated to the public (patents).

...I found the title sadly misleading. No Chapter 11 bankruptcy for Disney.;_;

However, that being said... even though Disney is still an evil corporation and amongst the most evil, this is a nice gesture on their part to make the compressed-air technology available to everyone.

What I'd like to know, however, is why they didn't release it into the public domain? Then again, this is Disney; they abhor the public domain, so it oprobably stands to reason that they wouldn't dare touch that prospect.

Then again, this is Disney; they abhor the public domain, so it oprobably stands to reason that they wouldn't dare touch that prospect.

Not necessarily so. They open-sourced their Panda3D game engine [cmu.edu], used most notably for their game Toontown Online.

Here's a bit from their FAQ:Panda3D was originally developed at the Disney VR Studio. Disney VR used a proprietary IRIX-specific system called DWD (Disney's World Designer) to create several DisneyQuest Virtual Reality Attractions, such as "Aladdin's Magi

The one thing I did like about black powder is the ability for controlled burns, allowing a much slower ascent for fireworks which light up on the way up. I don't think that's possible with this technique.

The WDI spokeswoman says "Disney isn't sure when its Central Florida theme parks could install or start testing the new fireworks launch system."
Actually, the air-launched fireworks are not completely new, but Disneyland is the first time they're using air for the whole (or majority of the) show. The first use was at Epcot down at Walt Disney World for the Illuminations: Reflections of Earth show - where the first "comet" effect that screams over the lagoon is air-launched from on top of one of the pavilion buildings. If you're walking in that area around 15 minutes before the show starts, they rope off the main pathway that passes under the launch area. You do hear a big fwoosh when it goes off. The last time this bit made Slashdot, some comments were debating the gas used - in this case they're compressing plain air.

The new Wishes fireworks show which has been playing since last Fall at the Magic Kingdom at WDW also planned to use the air launch, but the cost of the installation was too much and traditional fireworks have been used. Unlike WDW where there's a sizable land buffer between residences and the parks, Disneyland has large neighborhoods of people surrounding it, and they exert pressure on the local government to make things more difficult (and expensive) for Disneyland. Wishes also introduces the concept of firing shells from within the park off buildings in Fantasyland, which makes for some spectacular effects if you're watching from back in that area.

Also related, Disney is working with a top national lab on fireworks that look just like normal pyro, but burn with much less smoke. While some shows use the smoke the fireworks produce for great effect, eliminating it could be nice for others. Another technology that has been slowly introduced is the use of shells that contain a sacrificial computer chip that syncs its timing upon launch and fires an electronic fuse when up in the air to obtain much more precise ignition timing than could be accomplished conventionally.

Overall, there's some very cool tech going on, but whether Disney chooses to use it all over the place is more of a question of practicality than simply because they have it, so it's good to hear they're donating some of the tech.

Who cares about the fireworks. Just think how far one of those compressors could launch a potatoe! This also presents an alternative to traditional guns. Forget plastic bullets, now you can kill/knockout your enemys with enviromentally friendly, biodegradable food staples. Where can I get one?

This refers, of course, to Mary Poppins, who was "Practically Perfect in Every Way", as anyone who has seen the movie will recall. Those of you with kids and a VCR, who have seen the damn movie at least 400 fricken times already and never want to see another dancing penguin for the rest of your fricken lives, will no doubt catch the reference right away.

And no, you can't watch "Hercules" either. Go read a book, for cryin' out loud.

At least they're doing something. After firing 250 animators, literally and arrogantly destroying their entire (irreplaceable) animation department (after some 80 years) claiming "2D animation is dead," (despite the fact there are over 400 animation studios in Japan) canceling a multi-billion dollar deal with Pixar and then, with a straight face, claiming "we can't make money on Monday Night Football," I suppose replacing the fireworks show tubes is quite an accomplishment for a $46 billion company.

This beats my tennis-ball-cannon by a longshot. It doesn't use black powder either but I don't get that height. I guess I will have to switch from lighter fluid to compressed air and see what that does for the height.